<?php
/**
 * Zend Framework
 *
 * LICENSE
 *
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://framework.zend.com/license/new-bsd
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@zend.com so we can send you a copy immediately.
 *
 * @category   Zend
 * @package    Zend_Feed_Reader
 * @copyright  Copyright (c) 2005-2011 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 * @version    $Id: EntryAbstract.php 23953 2011-05-03 05:47:39Z ralph $
 */

/**
 * @category   Zend
 * @package    Zend_Feed_Reader
 * @copyright  Copyright (c) 2005-2011 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 */
abstract class Zend_Feed_Reader_EntryAbstract {
	/**
	 * Feed entry data
	 *
	 * @var array
	 */
	protected $_data = array ();
	
	/**
	 * DOM document object
	 *
	 * @var DOMDocument
	 */
	protected $_domDocument = null;
	
	/**
	 * Entry instance
	 *
	 * @var Zend_Feed_Entry_Interface
	 */
	protected $_entry = null;
	
	/**
	 * Pointer to the current entry
	 *
	 * @var int
	 */
	protected $_entryKey = 0;
	
	/**
	 * XPath object
	 *
	 * @var DOMXPath
	 */
	protected $_xpath = null;
	
	/**
	 * Registered extensions
	 *
	 * @var array
	 */
	protected $_extensions = array ();
	
	/**
	 * Constructor
	 *
	 * @param  DOMElement $entry
	 * @param  int $entryKey
	 * @param  string $type
	 * @return void
	 */
	public function __construct(DOMElement $entry, $entryKey, $type = null) {
		$this->_entry = $entry;
		$this->_entryKey = $entryKey;
		$this->_domDocument = $entry->ownerDocument;
		if ($type !== null) {
			$this->_data ['type'] = $type;
		} else {
			$this->_data ['type'] = Zend_Feed_Reader::detectType ( $feed );
		}
		$this->_loadExtensions ();
	}
	
	/**
	 * Get the DOM
	 *
	 * @return DOMDocument
	 */
	public function getDomDocument() {
		return $this->_domDocument;
	}
	
	/**
	 * Get the entry element
	 *
	 * @return DOMElement
	 */
	public function getElement() {
		return $this->_entry;
	}
	
	/**
	 * Get the Entry's encoding
	 *
	 * @return string
	 */
	public function getEncoding() {
		$assumed = $this->getDomDocument ()->encoding;
		if (empty ( $assumed )) {
			$assumed = 'UTF-8';
		}
		return $assumed;
	}
	
	/**
	 * Get entry as xml
	 *
	 * @return string
	 */
	public function saveXml() {
		$dom = new DOMDocument ( '1.0', $this->getEncoding () );
		$entry = $dom->importNode ( $this->getElement (), true );
		$dom->appendChild ( $entry );
		return $dom->saveXml ();
	}
	
	/**
	 * Get the entry type
	 *
	 * @return string
	 */
	public function getType() {
		return $this->_data ['type'];
	}
	
	/**
	 * Get the XPath query object
	 *
	 * @return DOMXPath
	 */
	public function getXpath() {
		if (! $this->_xpath) {
			$this->setXpath ( new DOMXPath ( $this->getDomDocument () ) );
		}
		return $this->_xpath;
	}
	
	/**
	 * Set the XPath query
	 *
	 * @param  DOMXPath $xpath
	 * @return Zend_Feed_Reader_Entry_EntryAbstract
	 */
	public function setXpath(DOMXPath $xpath) {
		$this->_xpath = $xpath;
		return $this;
	}
	
	/**
	 * Get registered extensions
	 *
	 * @return array
	 */
	public function getExtensions() {
		return $this->_extensions;
	}
	
	/**
	 * Return an Extension object with the matching name (postfixed with _Entry)
	 *
	 * @param string $name
	 * @return Zend_Feed_Reader_Extension_EntryAbstract
	 */
	public function getExtension($name) {
		if (array_key_exists ( $name . '_Entry', $this->_extensions )) {
			return $this->_extensions [$name . '_Entry'];
		}
		return null;
	}
	
	/**
	 * Method overloading: call given method on first extension implementing it
	 *
	 * @param  string $method
	 * @param  array $args
	 * @return mixed
	 * @throws Zend_Feed_Exception if no extensions implements the method
	 */
	public function __call($method, $args) {
		foreach ( $this->_extensions as $extension ) {
			if (method_exists ( $extension, $method )) {
				return call_user_func_array ( array ($extension, $method ), $args );
			}
		}
		require_once 'Zend/Feed/Exception.php';
		throw new Zend_Feed_Exception ( 'Method: ' . $method . 'does not exist and could not be located on a registered Extension' );
	}
	
	/**
	 * Load extensions from Zend_Feed_Reader
	 *
	 * @return void
	 */
	protected function _loadExtensions() {
		$all = Zend_Feed_Reader::getExtensions ();
		$feed = $all ['entry'];
		foreach ( $feed as $extension ) {
			if (in_array ( $extension, $all ['core'] )) {
				continue;
			}
			$className = Zend_Feed_Reader::getPluginLoader ()->getClassName ( $extension );
			$this->_extensions [$extension] = new $className ( $this->getElement (), $this->_entryKey, $this->_data ['type'] );
		}
	}
}
